Since the inception of automobiles, motorists have caused or experienced automobile accidents. Head-to-head collisions are some of the deadliest accident types. These accidents most commonly occur when a motorist enters into a divided highway or a one-way roadway in the incorrect direction. These accidents are disproportionally caused by impaired or aged motorists. As a result, there is a great need to alert motorists who unintentionally travel in the incorrect direction.
Motorists, cyclists, and pedestrians utilize various infrastructure elements, such as signs, markings, and markers, to guide them down a road, lane, path, or hallway. One of the most effective elements is that of surface markings or markers. The most common types of applied surface markings on the roadway are longitudinal and lateral lines, symbols, messages, and raised or embedded pavement markers. These markings provide both guidance and warning messages specific to the viewer's need. Unlike a vertically posted sign, surface markings are applied and viewed horizontally on the surface. The result is that viewers traveling in either direction receive the same visual message. At best, these types of markings have limited effectiveness. At worst, these types of markings are confusing to the viewer and impact to their safety.
The color and content of a marking is another important factor for providing a clear concise message to the viewer. The color of these markings provide crucial guidance and warning information to motorists. Yellow markings divide traffic traveling in the opposite direction. White markings are used for lateral and edge lines, symbols, messages, and dividing traffic traveling in the same direction. Red, when used, indicates ‘danger’ and is often associated with stop, do not enter, or wrong way warnings.
In an effort to reduce horrific accidents on roadways, some agencies deployed intelligent transportation devices like that of radar systems placed in limited locales such as select highway exit ramps. These detect incorrect direction travel and activate a digital warning sign. Though these may be effective, they are extremely expensive and can only be installed in limited environments.
Roadway markings in their current form do little to prevent or alert motorists of incorrect direction travel. Longitudinal and lateral lane lines do not provide clear orientation of the travelway's direction. The orientation of symbols and legends do provide some conspicuity of the travel direction to normal non-impaired motorists, but are only slightly effective and nearly undistinguishable to an impaired motorist. Agencies are reluctant to install additional conventional bidirectional roadway markings since they are concerned with distracting or confusing a motorist traveling in the correct direction.
Supplemental raised or embedded markers are periodically installed on or parallel to the lane lines to aid drivers in identifying the markings during nighttime or in adverse weather conditions. These markers are traditionally the same color as the line they are placed on or next to. Some agencies utilize bidirectional markers that display white in one direction and red in the other to assist in incorrect direction alert. However, at a norm of 40-foot centers and less than 8 square inches of displayed color, these have been found to be an inadequate alert device in many cases.
Currently, there is no device specifically designed to provide a bidirectional marking with a unidirectional message dependent upon the direction of travel by the viewer. Surface markings or markers are limited to provide a single message, seen from both directions.